However, TVLine is now reporting that Rosenbaum will in fact make his long awaited comeback in the two hour series finale.

“I’m delighted to return for the series finale,” said Rosenbaum. “I’m simply doing it for all of the fans out there who made ‘Smallville’ the great success it is. I appreciate all of their passion, their relentlessness, and even their threats. Ha ha.”

“I can’t wait to hug the old crew back in Vancouver one last time and see all of my old friends once again," continued Rosenbaum. "Oh, and for Lex to become the bad-ass he’s destined to be.”

“It feels like the stars are aligning, literally," wrote "Smallville" showrunners Kelly Souders and Brian Peterson. "We couldn’t be more excited. And as far as the way he returns… there’ll be no doubt about how Lex becomes the great rival in Clark Kent’s life. He is the villain of the story.”

Several former cast members of "Smallville" have already made appearances in the its tenth and final season, including John Schneider, Annette O’Toole, John Glover and James Marsters. Laura Vandervoort also reprized her role as Kara/Supergirl earlier in the season and will return for one final appearance in the series, as will Callum Blue as Zod.

Now, the only main character not coming back to the series is Kristen Kreuk’s Lana Lang, who last appeared during the eighth season of "Smallville." While other reports have already stated that Kreuk will not return again, Rosenbaum’s reversal may prove that anything is possible as the long running superhero series finally comes to an end on Friday, May 13.